Flexible pouches formed of a plastic or foil are used to package a variety of products including consumable liquids and other edible products. In order to extend the shelf life of the package, the liquid and/or other products must be packaged in the absence of oxygen. The presence of oxygen in the filled pouch increases the chance of bacteria forming, or may affect the taste. Previously known packaging systems included a pre-filling purging station, a filling station, and a post-filling purging station. In the pre-filling purge station and the post-filling purge station, a purging gas such as carbon dioxide (CO2) or nitrogen (N2) is directed into the pouch at a high pressure. However, due to the high pressure of the purging gas, residual amounts of oxygen remain within the pouch due to the turbulent mixing of the oxygen with the purging gas. These residual amounts of oxygen remaining in the pouch considerably shorten the shelf life of the packaged product.
In addition, when the flexible pouches are filled with a product that is a particulate, such as powdered cheese, powdered drink mixes or the like, it is difficult to accurately fill the pouch with the correct amount of product. Specifically, the calibration required by a feeder so as to be able to dispense a precise amount of product is difficult to maintain at high speed fillings. Further, as the product is a particulate such as a powdered product, a portion of the amount dispensed typically remains airborne and does not enter the pouch.
It is therefore an objective of this invention to provide an apparatus and method which thoroughly purges the oxygen in a flexible pouch, and accurately fills the pouch with a particulate product.